Dandy roll



y P. s. SINCLAIR El AL 2,039,610

DANDY ROLL Filed Oct. 5, 1934 2 Sheets-Shet 1 INVENTORi ATTORNEY y 1936! P. s. SINCLAIR ET AL DANDY ROLL Filed Oct. 5, 1934 2 Sheets-Sheet 2 INVENTORS, flier S Sz'zzc/az; and

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ATTORNEY.

' which Patented May 5, 1936 UNITED STATES DANDY ROLL Peter S. Sinclair and Kenneth C. Gosling, Holyoke, Mass., assignors to The Sinclair Company, Holyoke, Masa, a corporation of Massachusetts Application October 3, 1934, Serial No. 746,633

15 Claims.

This invention relates to dandy-rolls employed in paper-making machines.

One of the objects of the invention is to strengthen a dandy-roll by means of the special construction employed herein.

It is not uncommon for a dandy-roll in use to become clogged with material from the paper web and to require cleaning. This is often done with a steam hose with the result that the temperature strains set up thereby cause the skeleton-like structure of the dandy-roll to break apart. These and other strains frequently damage a dandy-roll. so much that it becomes valueless for any further practical use.

It is therefore an object of the present invention as already stated to increase the mechanical strength of a dandy-roll inzorder to resist the strain described in the foregoing paragraph and also other strains of whatever character.

It is also an object of the invention to maintain the maximum drainage compatible with the desired strength, an object always considered desirable in such devices, and even to improve such.

. drainage by the novel construction described 25 herein.

It is furthermore an object of the invention to provide means for producing a soldered joint that can be made quickly and which will be stronger and more durable than the usual soldered joint in such devices.

Another object of the invention is to provide means for permitting a certain amount of expansion in a dandy-roll, such as that due to temperature changes, without the usual corresponding changes in form and resulting mechanical strains. More specifically it is an object of the invention to provide one or more expansion loops which will permit expansion without undue mechanical strain.

These and other objects of the invention will readily appear to those skilled in the art to'which it appertains by a consideration .of one embodiment thereof described in the following specificainthe accompanying drawings in tion and shown Fig. 1 is a sideelevation of a dandy 'roll partly broken away; j Y and parts connected therewith;

' a 3 an ed sectional-vi the line 3-4 of Fig. 1;

Fig. 3;

(Cl. 9H8) s s .0: Fig. 4 showing one of the rods and winding wire;

Fig. 6 is a section showing the parts of Fig. 5 as seen from the right of Fig. 5; and

Fig. '7 is an enlarged view of one of the expan- 5 sion loops.

Referring to the drawings more in detail the dandy-roll is supported by two-short shafts H and I2 each carrying a head as indicated by the reference characters l3 and M respectively. 1 0 While this type of construction is shown in the drawings, it is to be understood that the invention maybe equally well applied to other types of construction as for example the type of construction which is commonly referred to as the open end type (if dandy-roll. The main supporting structure of the dandy-roll is the helically wound strip I5 extending from the head l3 at one end of the dandy-roll to the head M at the other end of the dandy-roll. This strip is preferably of an elongated cross section as shown in Fig 4 to provide maximum rigidity and stiffness and at the same time to permit maximum drainage by offering minimum obstruction to the passage of water from the outside of the roll toward the center. This is accomplished by winding the stripon edge thus presenting to the entrance of the water its smallest dimension.

The outer edges of the helix serve to support a plurality of longitudinally extending rods 18 which are also preferably elongated'so that they also present to the lnflowing water their smallest dimension. The cross-sectional form of the rods I6 is shown in the drawings as somewhat tri-' angular, that is, the portion at the top or nearest the outside circumference of the dandy-roll, in-

. dicated at IT, is somewhat smaller than the bot-' tom of the rod, indicated at l8. This form provides less obstruction to the inward flow of water near the outside of the dandy-roll where it is 40 most likely to get clogged up and the necessary I size to furnish the requisite strength is spaced a littlefarther from the outside. The form shown ,also seems to provide greater rigidity and strength to the complete structure than the same weight of metal of rectangular cross section. The under A v v I side'or the bottom is provided with a groove I! Fig. 2 is an end View thereof m in head, I which is primarily of value msoldermg the rods 16 to the helix IS. The groove aflfords an oppor- I5 and the rod l6 'niuch'morefreely than would be 1 surfaces ih'contact with eachother. The special features of construction just described with spe'ct tamerodlfi are best seen in rig. s.

notches 28 in its outer edge for the lower set of members 20, 2|, 22, 23, etc., deep enough to receive two of the reinforcing members, one on top of the other, as is clearly shown in Fig. 3. It is preferable to have the reinforcing members cross the successive turns of the helix midway between a pair of rods l6, I6. This is shown in Fig. 1 and in Fig. 3. These reinforcing rods are positioned diagonally, that is, they extend in the direction of a helix having a very large pitch. This requires that each reinforcing member cross each successive turn of the helix at least one of the rods l6 further around circumferentially and one rod is usually preferable to more than one. It will thus be seen that the lower set of rods 20, 2|, 22, 23, etc. are positioned helically in the direction of a left-hand screw having a very large pitch. The successive members 20, 2|, 22, etc. are shown in Fig. 3 and more clearly in Fig. 1 as being spaced apart circumferentially a distance equal to 4 of the rods it which gives a symmetrical structure as will more clearly appear hereinafter.

The successive turns of the helix l5 are also provided with notches 23 for the upper set of reinforcing members 24, 25, 26, 21, etc. which are about half the depth of the notches 28 so as to receive one of the members only. This upper set of reinforcing members is similar to the lower set in that they cross the turns of the helix midway between the rods [8, in that they extend around circumferentially one rod in extending from one turn of the helix to the next, and in that the adjacent members are spaced 4 rods apart circumferentially. The upper rods differ from the lower rods, first, in that they are positioned slightly nearer the circumference so that the two sets of reinforcing members cross each other readily, one above the other, and in that the upper set of reinforcing members extend in the direction of a right-hand screw instead of a left-hand screw. It is desirable that the.two sets of reinforcing members cross each other in one of the deep notches 23 provided in the helix as shown, for example, where the lower reinforcing member 2|" and the upper reinforcing member 24 cross each other (see Figs. 1 and 3). With such an arrangement the lower and upper *reinforcing members cross each other at every other turn of the helix and at the intermediate turns they cross the helix separately. The angular relationship of the mutually reinforcing parts of the structure, a lower reinforcing member 2|, an upper reinforcing member 24, and a portion of one turn of the helix I5 is approximately that of an equilateral triangle. The crossing of the ,lower and upper members at one of the turns of the helix is not conveniently attained in every case all around the circumference due to the fact that the number of rods in different dandy-rolls is different but so far as it is attainable it is preferable.

While the reinforcing members 23 to 21 are shown positioned beneath the rods it it has been found somewhat easier, all things considered, to solder the rods IS in place first and then cut the proper notches midway between the rods and push the reinforcing members in endwise under the rods and then solder them in place.

The structure already described is for providing strength to withstand strains. In order to reduce the amount of expansion, as well as to provide strength, there are preferably provided one or more expansion loops 33. Each of these loops may be a .piece of the same material of which the helix is constructed bent into circular form and then each of the ends formed into a reverse bend 35 terminating in an ear 34. The helix I5 is out near the end of the dandy-roll as shown in Fig. 7 and the two ears 34 are soldered or otherwise secured to the helix l5 at opposite sides of the cut. The resiliency of the expansion loop 33 permits the two ends of the helix I5, as shown in Fig. 1, to move toward and away from each other with very little distortion or bending of the rods It. The number of these expansion *loops may be varied somewhat at the choice of the designer but very satisfactory results have been obtained by using not more than three or four such loops near each end of the roll. We prefer to place the first loop three or four turns of the helix from the end of the dandy-roll, the second loop about three and one-half turns further along, and each additional loop about the same distance from the preceding one. The reverse bend 35 should be a curve and not a sharp corner so that the bending of the loop will be taken up by the whole loop and not be largely concentrated at the point 35. This is one reason why it is difficult to obtain as satisfactory results with a loop formed in the helix itself.

The rest ofthe construction is very similar to standard dandy-roll construction. The structure as a whole is rotated while notches 30 are cut in the rods it onto which is then wound a winding wire 3|. This winding wire is preferably rectangular in cross section to facilitate drainage and is provided with rounded edges as st shown in Fig. 6. And finally a fine wire or so een 32 is placed over the winding wire and sewed or otherwise fastened at the seam to complete the finished structure.

In operation, the dandy-roll construction hereinbefore described possesses rigidity, strength, and permanence in wear to a degree which far exceeds any dandy-roll with whichthe inventor of the present device is familiar. -It is to be particularly observed that the position of the reinforcing members, extending both ways, in

the direction of a right-hand screw and in the direction of a left-hand screw, in the notches of the helix, provides in itself a considerable de gree of rigidity regardless of the solder in bolding theparts in theproper position. Thus. it is and greatly improves the drainage while the grooves therein both speeds the work of soldering and improves the quality-of the finished joint.

'While the helix l5 has been described as of an elongated or rectangular cross section the improvements described herein may also be used with a helix of circular cross section.

It is to be understood that the embodiment of the invention set forth in the foregoing description has been selected'for purposes of 11- lustration only and various changes may be made herein without departing from the spirit and scope of the invention as defined in the subjoined claims.

We claim:

1. In a dandy-roll, a supporting structure in the form of a helically disposed member of a very small pitch and two sets of helically disposed reinforcing members of very large pitch, one set of said helically disposed reinforcing members extending in the direction of a righthand screw and the other set of said helically disposed reinforcing members extending in the direction of a left-hand screw.

2. In a dandy-roll, a helically wound flat strip, longitudinal rods fastened to the outer edge of said strip, a winding wire around said rods, a wire screen positioned around said winding wire, and members for reinforcing said helically wound strip extending across the outer edges thereof in both diagonal directions.

3. In a dandy-roll, a helically wound flat strip, longitudinal rods fastened to the outer edge of said strip, a winding wire around said rods, a wire screen positioned around said winding wire, a set of helically disposed reinforcing members extendingacross the outer edges of said helically wound flat strips, the direction of said membersbeing more longitudinal than circumferential, and a second set of helically disposed reinforcing members extending across the edges of said helically wound flat strips, the direction of said members also being more longitudinal than circumferential, one of said sets of helically disposed members being in the direction of a right-hand thread and the other in the direction of a left-hand thread. i

4. In a dandy-roll, a supporting structure in the form of a helically disposed fiat strip of a small pitch wound on edge, a plurality of longitudinal rods secured to the outer edges of the convolutions of said helix, and two sets of helically disposed reinforcing members of very large pitch, one set of said members extending in the direction of a right-hand thread and the other set of said members extending in the direction of a left-hand thread, the convolutions of said helically disposed strip having two sets of notches in the outer edges thereof staggered in position with respect to said rods for the reception of said reinforcing members, one set of notches being deeper than the other for one set of members and the other set being more shallow for the other set of members, the 'crossing of the members being at the edges of the strip and in the deeper notches.

5. In a dandy-roll, a supporting structure having a plurality of supporting means extending in a generally circumferential direction, each of said means having the cross-sectional form of a flat strip, and a plurality of elongated longitudinal rods extending transversely of said supporting means with the longer dimensions thereof disposed radially and with the inner edges thereof secured to the outer edges of said supporting means, each of said rods having a shallow groovealong the inner edge thereof.

6. In a dandy-roll, a supporting structure in the form of a helically disposed flat strip of a very small pitch wound on edge, and a plurality of longitudinal rods secured to the outer edges of the convolutions of said helix, each rod having a substantially triangular cross section with a narrow base positioned against the helix and with the opposite apex positioned outwardly from the helix and said cross section having a shallow recess in the base thereof.

7. In a dandy-roll, a supporting structure in the form of a helix, longitudinal rods positioned across the outer edges of the convolutions of the helix and secured thereto, and an expansion loop positioned in said helix near the end thereof.

8. In a dandy-roll, a supporting helical structure formed by winding a flat substantially rectangular strip on edge, said strip being provided with a plurality of expansion loops near each end thereof.

9. In a dandy-roll, a supporting structure in the form of a helix of fiat strip wound on edge, a plurality of longitudinal rods extending across the outer edges of the successive helices and secured thereto, the outer edges of said helices havingv notches provided therein midway between said rods, and two sets of reinforcing rods positioned in said notches and extending from one end of the dandy-roll to the other, one set extending angularly with respect to a line parallel to the axis of the dandy-roll in the direction of a right-hand screw, and the other set extending angularly with respect to a line parallel to the axis of the dandy-roll in the direction of a lefthand screw.

10. In a dandy-roll, a supporting structure in the form of a helix of flat strip wound on edge,

a plurality of longitudinal rods extending across the outer edges of the successive helices and secured thereto, the outer edges of said helices having notches for reinforcing members provided therein, a pair of reinforcing members one positioned above the other in said notches, one of said members extending angularly with respect to a line parallel to the axis of said dandy-roll in the direction of a right-hand screw, and the other of said members extending angularly with respect to a line parallel to the axis of said dandyroll in the direction of a left-hand screw, wherebyv said helix is held at the point of crossing of said members from movement longitudinally of said dandy-roll in either direction.

11. In a dandy-roll, a supporting structure in the form of a helically disposed flat strip of a very small pitch wound on edge, each turn of said helix having a plurality of notches spaced circumferentially around the outer edge thereof, and two sets of reinforcing members positioned in said notches, each member of one set extending in one diagonal direction from a notch in one of said turns to a notch in the adjacent turn, and each member of the other set extending in the other diagonal direction from a notch in one of said turns to a notch in the adjacent turn,

the members of one set crossing the members of v the other set in the notches in the helix.

helix and secured thereto, said turns having a plurality of notches in the outer edges thereof positioned midway of said rods, a set of diagonally disposed reinforcing members positioned in said notches and extending from one end of the dandy-roll to the other, and a second set of diagonally disposed reinforcing members positioned in said notches and also extending from one end oi. the dandy-roll to the other, the two sets of reinforcing members extending in opposite diagonal directions, substantially all of the crossings of members of one set with members of the other set being in notches of the helix.

14. Ina dandyroll, a supporting structure in the form of a helically disposed flat strip wound on edge, a plurality of longitudinal rods extending across the outer edges of the turns of said helix and secured thereto, said turns having a plurality of notches in the'outer edges thereof positioned midway of said rods, a set oi. diagonally disposed reinforcing members positioned in said notches and extending from one end of the dandy-roll to the other, and a second set of diagonally disposed reinforcing members positioned in said notches and also extending from one end of the dandy-roll to the other, the two 7 sets of reinforcing members extending in opposite diagonal directions and crossing the turns of the helix at the same point in substantially a minimum of fifty percent of the crossings.

15. In a dandy-roll, a supporting helical structure formed by winding 9. flat substantially rectangular strip on edge, a plurality of longitudinal rods extending across the outer edges of the successive helices and secured thereto, the outer edges of said helices having notches provided therein midway between said rods, and two sets of reinforcing rods positioned in said notches and extending from one end of the dandy-roll to the other, one set extending angularly with respect to a line parallel to the axis of the dandy-roll in the direction of a right-hand screw, and the other set extending angularly with respect to a line parallel to the axis of the dandy-roll in the direction of a left-hand screw, said helical strip being provided with expansion loops near each end thereof.

PETER S. SINCLAIR. KENNETH C. GOSLING. 

